Parachutes



Jan. 15, 1963 D. T. BARISH 3,073,555 I PARACHUTES Filed Sept. 16. 1957 4 Sheets-Sheet 1 v INVENTOB flea ski 7: 43am 5i ATTORNEY Jan. 15, 1963 Filed Sept. 16. 1957 D. T. BARISH PARACHUTES 4 Sheets-Sheet 2 INVENTOR Java/142i TI 547;54

ATTORNEY Jan. 15, 1963 D. T. BARISH 3,073,555

PARACHUTES Filed Sept. 16. 1957 4 Sheets-Sheet :s

INVENTOR 041/011 73 Bant'si ATTO R N EY Jan. 15, 1963 D. T. 'BARLSH 3,073,555

' PARACHUTES Filed Sept. 16. 1957 4 Sheets-Sheet 4 INVENTOR. David 1. Bard /7 ,4 TTORNEK United States Patent Ofiiice 3,073,555 Patented Jan. 15, I963 3,073,555 PARACHUTES David Theodore Barish, New York, N.Y., assignor, by direct and mesne assignments, to Barish Associates, Inc., New York, N.Y., a corporation of New York Filed Sept. 16, 1957, Ser. No. 684,262 27 Claims. (Cl. 244-145) This invention relates to parachutes, and particularly to parachutes formed of peripherally spaced flexible panels capable of autorotation.

In the US. Patent 2,797,885 issued July 2, 1957, to David Theodore Barish, entitled Vortex Ring Parachute, there is disclosed a flexible panel type of parachute in which the panels are substantially segmental, connected at their apices and at their peripheral margins, with the camber of each panel varying directly with the radius, While the tangent of the chord incidence varies inversely with the radius. While this has highly satisfactory performance, it has certain features affecting its favorable characteristics. For instance the panels of the invention of said patent were formed from initially generally flat substantial segments without axial overlap except at their apices. The ultimate camber of the panels after deployment is an adjustment between the tensions of the attachment points and the initially flat panels as affected by aerodynamic forces. The use of the twisted chord plane causes essentially zero incidence with respect to the relative wind. As a result, an appreciable amount of the lift is derived by camber, after autorotation becomes established.

It is among the objects of this invention: to improve the parachute of said patent; to provide a parachute using the autorotational principle to improve the drag characteristics, while also securing dependability, low cost, low snatch forces, low opening shock, anti-squidding and high stability for a given weight and/ or volume of package, and without introducing any additionally disadvantageous problems; to provide a parachute formed of flexible panels which are pre-shaped and contoured to have chordwise camber and radial curvature; to provide in a paneled parachute a central predeterminedly adjusted suspension line, usualy of about the same length as the divergent peripheral suspension lines, efiecting an axial dimple in the center of the canopy and improving the opening characteristics and increasing the radial camber of the respective panels and thereby assisting in the prevention of oscillations of the parachute during the descent; to provide a parachute canopy of spaced preshaped panels each attached to an adjacent panel by a peripheral line extending between the leading and trailing edges of the respective panels of a pair to which a peripheral suspension line is attached at a point closer to the leading edge of one panel of such pair of adjacent panels than to the trailing edge of the other panel, to impart a predetermined angle of incidence to said one panel upon deployment, with consequent acceleration of entry into autorotation; to provide a parachute of flexible panels having relatively wide margins and relatively narrow apices, with the panels each twisted so that the narrow apices are parallel to the axis of the parachute canopy, for strength and ease of anchorage with avoidance of axial overlapping, (by which is meant that at any point of one panel one cannot penetrate another panel by means of a line projection parallel to said axis), and with enhancement of the radial length of the tilted portion of each panel to take better advantage of the preset angle of incidence thereof; to utilize in a parachute a series of flexible panels which are each of low porosity in contrast to the conventional porous materials of the prior art parachutes and with related enhanced eiiiciency; to provide a parachute of spaced flexible panels connected at their apices and at their peripheral margins by peripheral lines with a supplemental circumferential inter-panel line longer than the marginal peripheral line, extending be tween the juxtaposed leading edge of one panel and the trailing edge of the next adjacent panel, at about twothirds (one-half to three-fourths), of the radial outward distance between the apices and the peripheral margins, serving three important functions: preventing tangling of the components of the parachute canopy, pulling the edges of adjacent panels together during opening to effect raise the solidity of the canopy to accelerate deployment, and preventing lufling of the panel edges after deployment; and many other objects and advantages of the invention will become more apparent as the description proceeds.

In the accompanying drawing forming part of thisdescription: a

FIG. 1 represents a fragmentary plan view of an illustrative initially formed panel section, showing the cuts formed therein by the removal of pieces to form internal; external, and peripheral edges of which the confronting internal edges are subsequently respectively joined to form the ultimate contoured and shaped panel of the invention, in an illustrative preliminary organization of the latter. FIG. 2 represents a plan view of the illustrative panel according to the invention, as assembled from the founda tion panel of FIG. 1, after the internal severed edges have been united to effect the shaping and contouring thereof.

FIG. 3 represents a section on line 33 of FIG. 2.

FIG. 3a represents a fragmentary longitudinal section through the panel of FIG. 2 showing the preformed contour thereof prior to inflation.

FIG. 312 represents a similar section through the panel in its inflated condition.

FIG. 4 represents a top plan view of the parachute canopy as formed by an illustrative form of the prelshaped and contoured panels, after twisting of the latter, under full deployment, showing the suspension lines attached to the marginal peripheral lines which connect the leading edge skirt points to the respective trailing edge skirt points of adjacent panels, to effect an-angle of incidence of each panel upon deployment, and showing the supplemental inter-panel circumferential lines of greater length between panels than said marginal peripheral lines between panels, extending between adjacent panels to prevent or minimize lufling, among its other functions, to be described, and showing the narrow inboard ends of the panels twisted so that at the common axis each is in a substantial plane parallel to such axis.

FIG. 5 represents a fragmentary plan of the central portion of the canopy showing the reinforcing bends in the respective inboard portions of the panel, in their sub stantially 45 chamfering in their relation to the central riser, for common juncture and attachment.

FIG. 6 represents a fragmentary section taken on line 6-6 of FIG. 5.

FIG. 7 represents a partially schematic side elevation of the parachute of the invention in its drawn-out compacted form as for packing, or as being withdrawn from a pack.

FIG. 8 represents a plan view of the parachute under partial deployment as taken on line 8-8 of FIG. 7."

FIG. 9 represents a side elevation of the partially collapsed, or inflated, parachute according to the invention in an intermediate stage of packaging, or deployment, similar to schematic FIG. 7, in which downward tension on the central riser and the suspension lines pulls the extremities of the panels downwardly under tension on the common swivel bearing, opposed upwardly by a light line connection to the general centers of the respective interpanel lines pulled in the other direction, which simultaneously pulls adjacent panels toward each other while forming general transverse fold or bend lines across each panel about which the panels are folded in response to the opposing tensions.

FIG. represents a side elevation of the fully collapsed concentrated folded parachute, in its first assembled condition for packing, in which the panels have been effectively folded about the generally transverse fold lines and the panels have drawn together in a substantially cruciform organization.

FIG. 11 represents, schematically, an end elevation of FIG. 10, with all lines omitted, for clarity.

FIG. 12 represents a plan of the parachute with its suspension and central riser lines to the swivel in one direction, in a zig zag organization leading into the twisted panels of FIGS. 14 and also disposed in a zig zag concentrated organization, and with the interpanel and light line connected to the rip cord of the parachute pack element upon which in zig zag organization all of the components are superposed in the formation of an ultimate package.

According to the present invention the individual panel is the basic element of the parachute, and it is preferred to form each so as to effect a built-in transverse as well as longitudinal camber. Of course the relationship of one panel to the next adjacent panel by the various connecting devices or lines is also an important part of the invention, as will be developed. While the panels may be otherwise formed, as by pre-cutting complemental halves of a complete panel, to illustrate the invention let it be assumed, as shown in FIG. 1, that a generally segmental foundation panel is stamped or cut out of the flexible material used in the parachute.

It may be noted at this point that although impressive functional results can be obtained with the invention by the use of conventional porous materials of the parachutes of the prior art, as presently being offered, it is a feature hereof that appreciably greater efficiency as regards all factors of the parachut are attained if the flexible material from which the panels are formed is substantially impervious and non-porous. In other words there is combined the complete flexibility of ordinary or conventional woven textile material, with substantially the impermeability of sheet metal. This is a definitive statement because the panels function like metal rotor blades in autorotation (which cannot tolerate much porosity). It will be evident, however, that metal blades cannot function in the present invention because they lack the flexibility of woven or like fabric, are bulky and hard to stow, and are much too heavy. They are also dangerous to personnel.

In defining non-porous it may be stated, according to the present invention, as a porosity not greater than 2 feet/ second at 2 inches of water pressure differential.

In forming the panels according to the present invention, each may be formed of two separate components placed back to back, as noted, but for illustrative purposes it is preferred to stamp or cut out a preliminary foundation panel 10, of the selected relatively imporous material. The foundation panel 10 has, at what will eventually be the apex of the panel, spaced tapering divergent tongues or tape-extensions, respectively 11 and 12 formed internally in mutual juxtaposition by convex shaped edges 13 and 14, meeting at 19, and formed externally by the respective concave edges 15 and 16 leading into the flared laterally peripherally extending points 17 and 18 of a peripheral marginal skirt portion 20. The sections 11 and 12 flare and taper outwardly from the common junction of edges 13 and 14 at 19. Thus, when as to be explained, edges 13 and 14 are joined together, the line of juncture is greater in length than the side or lateral edges 15 and 16, to force both a lateral and a longitudinal camber in the narrow inboard end of the panel formed by the juncture of tongues 11 and 12, at 4, as indicated in part by the sections shown in FIG. 3 and 3a.

The foundation panel 10, at the outer wider peripheral margin end 20 thereof, is provided with at least one, and preferably a plurality of generally wedge-shaped slots on each side of the center line of the foundation panel, providing longitudinally divergent edges as at 21-22, 23-24, and a median wedge-shaped slot providing curved divergent edges 2526. It will be understood that the right hand side of the foundation panel shown in FIG. 1 will have corresponding wedge-shaped slots to those forming edges 21-22 and 23-24, as well as the peripherally extending point 18.

In forming the panel 10' from the foundation panel 10, just described, as shown in FIG. 2, the internal confronting edges 13 and 14 are stitched or otherwise secured together, as at 4, and the confronting edges 21-22, 23-24 and 25-26 are similarly secured together as shown at 5, 6 and 7, respectively. This series of contourdetermining darts, 5, 6 and 7 in the skirt portion 20 draws in the outer periphery of the panel, shaping the skirt portion in a downward curvature, while at the same time the panel will acquire a built-in camber chordwisely thereof, with the camber increasing from the narrow inner or inboard end 30 toward the peripheral margin or skirt 20 and maintained under tension by the concave curvature of the side edges 15 and 16.

The complete panel 10 thus formed has a narrow, tapelike cambered small inboard end 30, and a wide, downwardly radially curved and chordwisely cambered peripherally pointed skirt 20. Preferably all of the lateral and peripheral margins of the completed panel 10' are secured to reinforcing cords, tapes or lines stitched or otherwise secured thereto.

In considering the individual panels 10' in the ultimate canopy, it will be understood that each has a leading edge and a trailing edge. Let it be assumed that the lateral edge 16 and terminal point 18 of the skirt portion comprise the leading edge, and the other lateral edge 15 and the terminal point 17 comprise the trailing edge. In assembling the desired number of panels 10' into a canopy, say, illustratively only, four thereof as shown in FIG. 4, the panels are laid out in a general cruciform pattern with all of the inboard ends 30 at or close to the common center. Each narrow inboard end 30 is twisted so that it lies in a general plane adjacent its terminus (ultimate apex), longitudinally generally bisecting the panel 10 and parallel to the central axis of the canopy formed by the panels with the trailing edge 15 above the leading edge 16. The twist is such that the upper edge 15 of the narrow end of each panel adjacent its small inboard end 30 is a continuation of the trailing edge 15-17 of the instant panel, so that the given panel has an angle of incidence at its inboard apex-forming end controlled throughout the radial length of the panels by the circumferential and marginal peripheral and the suspension lines, to be described. As noted the panel twists outboard toward its marginal end 20 causing the chord of the panel toward its outboard end to tend toward the perpendicular to the axis. Of course inboard refers to that section of the panels toward the central axis, whereas outboard refers to that section of the panels toward the periphery of the panels.

The illustrative four twisted generally vertical inboard ends 30 of the respective panels are placed in mutual juxtaposition to each other and to a central riser or suspension line 33, to which all of said ends are aflixed. As shown, in an illustrative anchoring arrangement, each narrow twisted tape-like end 30, adjacent to its terminus is chamfered downwardly, preferably, as at 10a, and this portion is bent at substantially a right angle to the body of the inboard end 30, as at 29, to overlie and to be secured to the inboard end portion 30 of the next adjacent panel 10', and to the central riser 33. The right angularly extending end portions 10a at the inboard ends of the panels thus present angularly divergent terminal ends. This anchorage may be augmented by auxiliary tapes and stitches.

The central riser or suspension line 33 provides means for dimpling the canopy, for controlling radial pitch. The anchoring procedure as described avoids axial overlapping of the panels and provides sutficient edging for structural integrity. While the central riser 33 may be of any length depending upon specific results desired, it has been found that excellent results are attained when it is not shorter than the suspension lines 35, to be described.

Relatively short marginal peripheral lines 34 are provided between adjacent panels, each extending from leading edge point 18 of one panel to the trailing edge point 17 of the contiguous panel. Suspension lines are provided, usually equal in number to the number of panels in the canopy. The peripheral suspension lines and the central riser 33 are anchored at their lower ends in swivel-bearing 37. Each suspension line 35 is anchored to a marginal peripheral line 34 at a point thereon closer to the leading edge point 18 than to the trailing edge point 17 of the contiguous panels to which the instant peripheral line 34 is attached. This insures that when load is applied to the suspension lines, upon deployment, the leading edge 16 at the periphery of the panels is pulled downwardly further than is the trailing edge of a given panel, so that a desired angle of incidence is effected on each panel coincident with deployment. Owing to the twist imparted to the narrow inboard end a desired distribution of angle of incidence is maintained substantially throughout the radial length of the panel.

With the organization of the canopy as so far described, it is composed of completely flexible components, of various lengths, each capable of bending and twisting and otherwise flexing, and there is therefore a possibility of tangling, which if not corrected or compensated for, may be hazardous. With the wide spaces between the panels the solidity of the canopy is low, with consequent retardation of blossoming after initial deployment. Further it has been found in some cases that after full deployment and with the canopy in autorotation, undesirable lufling of the panel edges occurs. Luffing is a stalling due to negative incidence. This, of course, is hazardous to the material of the panels, and adversely afiects the drag of the canopy. It is an added feature of the invention that all of these potentially undesirable attributes are resolved by the provision of supplemental inter-panel circumferential lines 36, each respectively extending between attachment points 43 and 44 respectively, at the leading and trailing edges respectively of each pair of adjacent panels. These points are located radially outward from the apex between the central riser or suspension line 33 and the margin of the skirt 20, as the only cross-connection between panels between the apex juncture 33 and the marginal peripheral lines 34. The inter-panel circumferential lines 36 are each longer than marginal peripheral lines 34.

The attachment points 43 and 44 on each panel lie in and define a fold line 40 across the panel. These points illustratively may be on the same chord line in the initial fabrication of the canopy. In response to tensions and tension compensations and adjustments in and on each twisted panel incident to the pressures of full and proper inflation, as opposed by the weight of the load transmitted through the central riser and the suspension lines from the swivel bearing, the apex and skirt of each panel assume datum attitudes and a mutual relation in space in which each panel is asymmetrical of a plane radial of the central axis of the canopy. In response to the same forces the attachment points 43 and 44 are relatively displaced longitudinally of the panel and the fold line 40 is elfectively cocked transversely of the panel so that it is angularly displaced from the normal to the mid-line of the panel. This is of importance in the fact that when, as later explained, the uninflated canopy is subjected to opposing tensions, one of which pulls the inter-panel lines in loops in one direction against the opposing tensions on the central riser and the suspension lines in the other direction, in packaging the parachute, the fold line 40 between points 43 and 44 assumes substantially the same cocked relation to the mid-line as exists under full inflation, and relatedly the inboard apex and the outboard skirt portion of each panel have the datum mutual relation established under full inflation. Therefore upon deployment after packaging the panels are respectively predisposed for optimum opening and prompt entry into autorotation.

Packaging of the parachute to secure effective opening and blossoming, without tangling, is facilitated by the invention. According to an illustrative procedure, with the swivel bearing 37 and lines 33 and 35 disposed forwardly,

.the inter-panel lines 36 are engaged by a light line, or

light lines, 39, of less tensile strength than that of the inter-panel lines 36, and drawn rearwardly. This forms each inter-panel line 36 into an open-ended loop, one leg of which engages the leading edge 16 of one panel 10' at attachment point 43, and the other leg of which engages the trailing edge 15 of the next adjacent panel 10' at attachment point 44. With the swivel bearing 37 and its attached lines held forwardly, tension rearwardly on the light line or lines 39 to the looped inter-panel lines 36 is operative on the respective panels at their attachment points 43 and 44 to develop the respective fold lines 40 with reference to the panels at their respective inboard connections to the axial central riser 33, and at their respective outboard connections to marginal lines 34 and the suspension lines 35. These relatively opposing tensions fold the panels about the fold lines 40 to bring the wider outboard ends of the panels toward the narrow inboard ends thereof. As noted the fold lines 40 are cocked relative to the mid-line of the panels and the folding brings the inner and outer extremities of each panel into their datum relative positioning. It is inherent in the disclosure, moreover, that the relative tension between the light line or lines 39 and the swivel bearing 37 is along the central axis of the assembly, and as the tension is developed, bringing the outboard and inboard portions of the respective panels relatively toward each other on opposite sides of the panel fold line 40, synchronously the respective panel attachment points 43 and 44 of the interpanel lines, and the attachment points of the peripheral marginal lines 34 and the attachment points of the suspension lines 35 to the latter, are each drawn radially inwardly toward the central axis of the assembly. The radial clustering of these several attachment points toward the common axis pulls the marginal outboard extremities 17 and 18 of each panel into mutual contiguity by folding the panel about a generally longitudinally fold line 41 thereof. The formation of folds about fold lines 40 and 41 and the shaping of the several panels into the general cruciform configuration shown in FIGS. 10 and 11, may be facilitated by suitable manual manipulations by the parachute packer. In any case it will be seen that the drawn together panels each have a closed rearward fold 40, a lateral edge formed of a closed told 41, whereas the forward edge 42 is formed mainly by two separate juxtaposed portions of the panel margin 20, so that it is open and disposed to admit air upon deployment.

In packaging the parachute from the basic drawn together organization as initiated in FIGS. 7, 8 and 9, and as completed in FIGS. 10 and 11, any desired further steps can be taken as may be desired to comport with the particular package organization which is sought. Illustratively, the preferred procedure is that illustrated in FIGS. 12 to 16 inclusive. Thus, as swivel bearing 37 is first packed forwardly, then the suspension lines 35 are zigzagged in one direction and packed forwardly. The canopy comprised of the drawn together panels 10 is gathered into a long bundle and zig-zagged into the pack. The circumferential lines 36 are drawn out rearwardly and laid on top of the contents of the pack, the pack folds are closed and the assembly is closed and held by the rip cord or wire to which the light strings or lines 39 forming the circumferential lines 36 into general loops are attached.

With the pack as thus described when the rip cord is pulled the light lines 39 attached to the inter-panel lines 36 and the latter as well are pulled out, pulling out the canopy, and these lines are held taut by the weight of the payload until the canopy begins to inflate. The inflation forces usually break the light lines 39. If this does not always occur immediately the weight of the load will cause same. In any case the start of the opening is followed by increasing opening, pulling out the suspension lines 35 and the central riser 33 and ultimately the swivel bearing 37, and the riser lines connected thereto and to the load.

It will be seen that the use of the light lines or strings 39 looping the inter-panel circumferential lines, in pulling the contiguous panels together minimizes the chance of tangling, raises the solidity of the canopy and accelerates the opening. After full blossoming the inter-panel circumferential lines may be in tension and substantially preclude lufling.

It may be noted that the central riser or suspension line 33 is relatively short enough so that in deployment the mergence of the narrow twisted inboard ends of the panels with the central riser is pulled axially downwardly to dimple the canopy. This improves opening by forcing the panels into a position in which the canopy readily blossoms. This also tends to bring the direction of the panel mid-section or mid-line (lines 4 and 7) normal to the axis, producing a greater component of the total lift in the desired direction. It is presently preferred that the central riser 33 be roughly of the same length as the respective suspension lines 35. Tests have indicated that this relationship gives presently peak drag coefiicients.

It is to be observed that the panels have concave edges 15 and 16 and the curvature of the side edges gradually increases at a non-uniform rate until a maximum is reached in the region of the greatest chord. This insures even cross-tension between the side edges 15 and 16 to maintain camber. Any chordal plane passes through the mid-line 4-7 perpendicular thereto at a reference point. The chord line is a straight line connecting said leading and trailing edges in a chordal plane. The region of greatest chord contains a point on the mid-line at which the chordal plane contains a chord of maximum length.

The inter-panel circumferential lines may be peripherally continuous if desired, but it is preferred to have them discontinuous and extend only from panel edge to panel edge across the space between panels. Under certain circumstances it may be found unnecessary to provide the inter panel lines, although these are provided for most sizes of parachute according to this invention, where the utmost elliciency is desired.

I claim as my invention:

1. A parachute comprised of a canopy formed of flexible panels, each relatively narrow at the inboard end and relatively Wide at the outboard margin, each panel containing at least one seam joining points on the material of the panel the loci of which are on lines on the flat material, at least one of which lines is effectively curved whereby the panel is initially shaped and contoured out of the flat during fabrication to have both chordwise and longitudinal camber.

2. A parachute as in claim 1 in which said lines are on edges of the flat material.

3. A parachute comprised of a canopy having a central apex and a peripheral margin and formed of flexible panels in which each panel has lateral side edges which when in an uninflated condition progressively curve outwardly away from each other from an apex to a margin.

4. A parachute as in claim 3, in which the progressive curve is non-uniform and increases with the chord of the panel.

5. A parachute comprised of a canopy formed of mutually azimuthally spaced but connected flexible panels each relatively narrow at the inboard end and relatively wide at the outboard margin, said narrow ends of the respective panels having a common juncture coaxial of the canopy, means at said common juncture holding said narrow inner ends in position substantially parallel to the central axis of the canopy so that each panel will have a predetermined leading edge and a trailing edge, a peripheral marginal line extending between the margins of adjacent panels and connecting the juxtaposed leading and trailing edges thereof, and suspension lines joined to the respective marginal lines between said leading and trailing edges at points closer to the leading edge of one panel than to the trailing edge of the adjacent panel.

6. A parachute formed of a plurality of flexible panels each narrow at the inboard end and wide at the peripheral marginal end, portions of the side edges of adjacent panels having peripheral spacing, said panel ends connected by external laterally concave edges, said inboard ends connected together in an apex, connecting means, connecting the respective marginal ends of the panels in azimuthal spacing in a canopy, a common fitting, suspension lines connected between said respective connecting means and said fitting pulling the peripheral marginal ends of said panels downwardly in a curved skirt, a central riser connected to said inboard ends of the panels at said apex and to said fitting for axially dimpling the canopy.

7. A parachute as in claim 6, in which said central riser is of substantially the same length as said suspension lines.

8. A parachute formed of azimuthally spaced but connected flexible panels each narrow at the inboard end conjointly defining a canopy apex and wide at the peripheral marginal end, each panel being held in a predetermined twisted position so that the chord of the narrow inboard end is in a plane, substantially, parallel to the axis of the parachute, said narrow inboard ends being attached together in a joint which contains said axis at said apex.

9. A parachute formed of azimuthally spaced but connected flexible panels, means connecting the panels at their respective inboard and outboard ends to form a canopy having an apex formed by said inboard ends, and inter-panel circumferential line means positioned between the inboard and outboard ends and extending between a pair of adjacent spaced panels to preclude flutter or lufiing, and means engaged with said line means under tension to loop said line means and to draw and transitorily hold said panels together to facilitate folding, packing and orderly deployment.

10. A parachute formed of azimuthally spaced but connected flexible panels each having a narrow inboard end and a wide outboard end with said inboard ends meeting in a common juncture substantially without overlap, a peripheral line connecting the wide outboard ends of adjacent panels, a suspension line connected to said peripheral line closer to one panel than to the adjacent panel of a pair of panels and thereby asymmetrically thereof, said panels having leading and trailing edges and being held in a predetermined twisted position so that the chordlines of the inboard ends lie in substantial planes parallel to the axis of the parachute, said twist being in a direction whereby the trailing edge of a panel is uppermost in said narrow ends and with said suspension line establishing a generally varying incidence to said panel throughout its radial extent from the narrow end thereof.

11. A parachute formed of pre-shaped and contoured panels each having a narrow inboard end and a wide outboard end, said outboard end having gores or darts bringing the outboard end into a downwardly curved contoured skirt at the outer peripheral edge of the parachute when the parachute is uninflated.

12. A parachute formed of circumferentially spaced flexible panels each having a narrow inboard end and a wide outboard end, each panel when uninflated having an entirely concave side edge over a major portion of its length.

13. A parachute comprised of a canopy formed of peripherally spaced but connected flexible panels, means connecting the panels together at a common axial center, line means connecting the panels together at peripheral margins, inter-panel line means connecting an edge of one panel with the edge of an adjacent panel as an intermediate connection disposed between said common center and said peripheral margins, in which said inter-panel line means has a given strength, and light line means of less strength than said inter-panel line means connected to the latter and simultaneously looping the latter and holding said panels together to enhance opening of the parachute, whereby upon deployment the blossoming of the parachute exerts tension on said inter-panel line means to rupture said light line means to permit full blossoming of said parachute with spacing of said panels.

14. A parachute comprised of a canopy formed of peripherally spaced but connected flexible panels, each panel having a narrow inboard end and a wide skirt portion connected by externally concave edges, said panels in assembly being twisted so that the narrow inboard ends are generally in planes parallel to the central axis of the parachute and are connected at a common axial center, line means connecting the peripheral skirt portions, suspension lines connected to said line means closer to one panel than to the other adjacent panel to impart an angular tilt to the respective panels to initiate and maintain autorotation of the canopy, supplemental line means extending between the edges of adjacent panels and located between the common center and the skirt portions to prevent lufiing of the panel edges, and a central riser connected to the said common axial center to axially dimple the canopy.

15. An autorotating parachute comprising a canopy having an axis and formed of circumferentially spaced but peripherally connected flexible panels each relatively narrow at an inboard end and relatively wide at an outboard margin and portions of the side edges of adjacent panels having peripheral spacing and each panel having a leading and a trailing edge, said narrow inboard ends lying in planes substantially parallel to said axis and each having an angularly divergent terminal end, said terminal end of one panel being juxtaposed to a portion of the narrow end of another panel and secured thereto and forming with other panels an apex joint surrounding said axis without extending across said axis.

16. An autorotating parachute comprised of a plurality of circumferentially spaced but peripherally connected flexible panels comprising a canopy, each panel having a relatively narrow inboard end and a relatively wide outboard end, portions of the side edges of adjacent panels having peripheral spacing, said ends connected by respectively leading and trailing edges, a central riser connected to the respective narrow ends to define a canopy apex, suspension lines conected to the outboard margins of the panels, said panels under proper inflation of the canopy and under payload weight on the central riser and the suspension lines assuming an attitude in space in which the leading edge is lower than the trailing edge and the wide marginal ends of the panels in projection radially of the axis of the central riser have a given rela tion to the narrow inboard ends at said apex, and means effecting a transverse fold line on each panel with reference to which the uninflated panels can be folded to establish substantially the same said given relation to enhance deployment of the canopy formed of folded panels.

17. A parachute as in claim 16 in which the fold line is established by the attachment of inter-panel lines at the respective leading and trailing edges of the respective panels and the folding is accomplished by opposing tensions on the inter-panel lines and on the suspension lines and the central riser.

18. A parachute as in claim 1 in which said seam extends longitudinally of the panel and substantially bisects same.

19. A parachute as in claim 18 in which the lateral side edges of the panel are essentially concave.

20. A parachute comprised of a canopy formed of azimuthally spaced but connected flexible panels, each panel having a narrow inboard end and of progressively increasing chord longitudinally from said narrow end toward a region of maximum chord, said panels when uninflated each having an entirely concave side edge between said narrow end and said region of maximum chord.

21. An autorotating parachute comprising a canopy embodying a plurality of radially extending circumferentially spaced panels each of which panels has a relatively narrow inner end located adjacent the peak of the canopy and a relatively wide outer edge located adjacent the periphery of the canopy, portions of the side edges of adjacent panels having peripheral spacing, means adjacent the periphery of the canopy connecting each panel to the adjacent panels in the canopy, suspension lines extending downward from the periphery of the canopy to a common point below the canopy, and a Cen ral riser connected to the peak of the canopy and to said common point and serving to draw the peak of the canopy and the inner ends of the panels downward at the center of the canopy upon deployment of the parachute.

22. An autorotating parachute comprising a canopy embodying a plurality of radially extending circumferentially spaced panels each of which panels has a relatively narrow inner end located adjacent the peak of the canopy and a relatively wide outer edge located adjacent the periphery of the canopy, portions of the side edges of adjacent panels having peripheral spacing, means adjacent the periphery of the canopy connecting each panel to the adjacent panels in the canopy, suspension lines extending downward from the periphery of the canopy to a common point below the canopy, and a central riser connected to the peak of the canopy and to said common point and serving to draw the peak of the canopy and the inner ends of the panels downward at the center of the canopy upon deployment of the parachute, said center line being of approximately the same length as said suspension lines.

23. An autorotating parachute comprising a canopy embodying a plurality of radially extending circumferentially spaced panels each of which panels has a relatively narrow inner end located adjacent the peak of the canopy and a relatively wide outer edge located adjacent the periphery of the canopy, portions of the side edges of adjacent panels having peripheral spacing, means adjacent the periphery of the canopy connecting each panel to the adjacent panels in the canopy, suspension lines extending downward from the periphery of the canopy to a common point below the canopy, and a central riser connected to the peak of the canopy and to said common point and serving to draw the peak of the canopy and the inner ends of the panels downward at the center of the canopy upon deployment of the parachute, the narrow inner ends of said panels presenting surfaces extending substantially parallel to the central riser of the parachute.

24. An autorotating parachute embodying a canopy having a central axis and a peak, the canopy being formed of a plurality of circumferentially spaced but connected flexible panels, each of said panels having a relatively narrow inboard end and a relatively wide outboard marginal end, portions of the side edges of adjacent panels having peripheral spacing, said narrow ends of the panels each lying in planes substantially parallel to the axis and presenting spaced leading and trailing edges with the leading edge at the narrow end of the panel at the bottom and the trailing edge of the panel at the top of said plane, means connecting the narrow ends together in fixed relation to said axis, means connecting the outboard ends of the panels together and forming with the panels a marginal peripheral line, and suspension lines extending downwardly from said peripheral line to a common means and under tension from said common means exerting greater downward tension on the leading edge than on the trailing edge of each panel whereby said leading edge adjacent to said margin is maintained lower than said trailing edge.

25. A parachute as in claim 24 and a central riser with said axis at the peak of the canopy connected to said leading edges of said narrow ends and to said common means, said riser under tension from said common means drawing the peak of the canopy and the narrow ends of the panels downward at the center of the canopy upon deployment while establishing tension on the leading edge of the panel to assure proper rotation of the canopy.

26. An autorotating parachute comprised of a canopy formed of a plurality of flexible panels each relatively narrow at its inboard end and relatively wide at the out- 20 board margin, portions of the side edges of adjacent panels being peripherally spaced, suspension lines connected to the-outboard marginal edges of the panels, a central riser, the lower ends of said central riser and suspension lines being arranged for connection to a load, each panel having chordwisely spaced leading and trailing edges, said narrow inboard ends lying substantially in planes parallel to said central riser with the leading edge at the bottom and the trailing edge at the top, said panels being twisted outwardly from the narrow inboard ends, said narrow inboard ends connected directly to each other and at both the bottom and the top edges thereof to said central riser at an apex whereby tension on the central riser axially dimples the canopy and places difierential tensions on the respective leading and trailing edges ofl each panel to enhance pitch distribution and aerodynamic eificiency of each panel.

27. A parachute as in claim 26, and suspension lines connected to the outboard margins of the respective panels whereby the canopy outboard margins are pulled downwardly as the canpoy is dimpled axially by said central riser.

References Cited in the file of this patent UNITED STATES PATENTS 2,258,797 Overbeke Oct. 14, 1941 2,770,432 Stevinson Nov. 13, 1956 2,797,885 Barish July 2, 1957 FOREIGN PATENTS 425,131 Italy Sept. 13, 1947 594,744 Great Britain Nov. 18, 1947 974,099 France Sept. 27, 1950 978,042 France Nov. 22, 1950 742,587 Great Britain Dec. 30, 1955 

1. A PARACHUTE COMPRISED OF A CANOPY FORMED OF FLEXIBLE PANELS, EACH RELATIVELY NARROW AT THE INBOARD END AND RELATIVELY WIDE AT THE OUTBOARD MARGIN, EACH PANEL CONTAINING AT LEAST ONE SEAM JOINING POINTS ON THE MATERIAL OF THE PANEL THE LOCI OF WHICH ARE ON LINES ON THE FLAT MATERIAL, AT LEAST ONE OF WHICH LINES IS EFFECTIVELY CURVED WHEREBY THE PANEL IS INITIALLY SHAPED AND CONTOURED OUT OF THE FLAT DURING FABRICATION TO HAVE BOTH CHORDWISE AND LONGITUDINAL CAMBER. 